I set up the Paypal 1 click upsell. But when I tested it, it forced me to make a Paypal account rather than checking out as a guest (see attached). How do I make it so that Paypal 1 click upsell does not go through a forced Paypal account?
Your customers have to have a PayPal account so that you can be able to charge them in a true One Click way.
It happens because on checkout PayPal creates a so called Reference between your merchant account and customer’s account for future payments, which allows One Click Upsells to be charged properly.